US4278401A - Blade for wind motors - Google Patents

Blade for wind motors Download PDF

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Publication number
US4278401A
US4278401A US05/962,731 US96273178A US4278401A US 4278401 A US4278401 A US 4278401A US 96273178 A US96273178 A US 96273178A US 4278401 A US4278401 A US 4278401A
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US
United States
Prior art keywords
blade
metal
cross
piece
plastics material
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US05/962,731
Inventor
Gabriele Martinelli
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Fiat SpA
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Fiat Societa Per Azioni
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Assigned to FIAT SOCIETA PER AZIONI reassignment FIAT SOCIETA PER AZIONI ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: MARTINELLI GABRIELE
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03DWIND MOTORS
    • F03D1/00Wind motors with rotation axis substantially parallel to the air flow entering the rotor 
    • F03D1/06Rotors
    • F03D1/065Rotors characterised by their construction elements
    • F03D1/0675Rotors characterised by their construction elements of the blades
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05BINDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2240/00Components
    • F05B2240/20Rotors
    • F05B2240/30Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/72Wind turbines with rotation axis in wind direction

Definitions

  • the present invention relates to blades for wind motors, in particular blades for attachment to a rotor hub of a wind motor.
  • An object of the present invention is to provide a blade for a wind motor having a secure connection between different materials such as metal and synthetic resin which have very different moduli of elasticity, so as to keep blade deformations under control, and to avoid in particular the occurrence of large amplitude aeroelastic vibrations.
  • the invention accordingly provides a blade for a wind motor having a metal attachment root, characterised in that the blade comprises a shell of plastics material having a number of internal transverse reinforcing ribs connected to at least two internal longitudinal members in which are embedded metal arms of the attachment root, which further includes a metal cross-piece to which said arms are attached, the attachment root also comprising a root member attached to said cross-piece for anchoring the blade to a rotor hub.
  • the blade construction according to the invention enables the wind loading exerted on the plastics blade shell to be transmitted through the ribs and longitudinal members to the metal cross-piece and thence to the attachment root member, with minimal blade deformation.
  • FIG. 1 is a longitudinal sectional view of a wind motor blade according to one embodiment of the invention.
  • FIG. 2 is a cross-section taken on line II--II of FIG. 1.
  • reference numeral 5 indicates generally a blade for a wind motor comprising a thin-walled shell of reinforced plastics material such as glass fibre reinforced plastics (g.r.p.) having an aerofoil section such as to be driven by wind flowing over the blade.
  • reinforced plastics material such as glass fibre reinforced plastics (g.r.p.) having an aerofoil section such as to be driven by wind flowing over the blade.
  • the blade 5 is supported internally by transverse ribs 9 the number of which will be chosen according to the length of the blade 5 and its desired rigidity.
  • the internal ribs 9 also serve to reinforce the blade shell, avoiding the formation of local creases and ensuring a smooth blade profile during operation under wind loading.
  • the ribs 9 are connected to internal longitudinal struts 11, also of a reinforced plastics material, which extend longitudinally within the blade shell and are connected to the internal surface of the blade shell along their opposite longitudinal edges.
  • the longitudinal struts 11, apart from having a blade-stiffening function, have chiefly a load-carrying function in that they transmit the load on the blade 5 to a rotor hub 13, shown partially in outline in FIG. 1 to which the blade is anchored by a metal fork attachment 15.
  • a load-carrying function in that they transmit the load on the blade 5 to a rotor hub 13, shown partially in outline in FIG. 1 to which the blade is anchored by a metal fork attachment 15.
  • the longitudinal struts 11 are, at their ends adjacent the hub 13, formed as hollow legs 17 of box section in which respective metal arms 19 of the fork attachment 15 are embedded.
  • the fork attachment arms 19 are of steel or other high strength material and are connected to a cylindrical cross-piece 21 of the same material, extending transversely between and projecting beyond the root ends of the arms 19.
  • the cross-piece 21 is hollow, having opposite end walls beyond the fork arms 11 from which respective cylindrical end pins 23 project, coaxially with the axis of the cross-piece 21.
  • the lengths of the two end pins 23 will generally be different from each other, being selected according to the blade configuration.
  • the cross-piece 21 and the end pins 23, including the parts of the arms 19 and spigot 25 attached to the cross-piece 21, are embedded in plastics material formed integrally with that of the blade shell 7 and struts 11.
  • a blade root spigot 25 is attached to the cross-piece 21 between the two arms 19 and projects longitudinally beyond the radially inner end of the blade for the purpose of anchoring the blade 5 to the hub 13.
  • the spigot 25 can have any shape according to the type of application of the blade.
  • the spigot 25 has a tapered frusto-conical shape and terminates in a screw-threaded shank for attachment of the spigot to the rotor hub 13.
  • the axis of the spigot 25 coincides with the longitudinal barycentric axis of the blade profile.
  • the lengths of the fork arms 19 will be selected according to the required stiffness of the blade and to the required capacity of the blade assembly to withstand the flexural stresses resulting from wind loadings in use of the blade.
  • the plastics-metal attachment structure of the blade 5 described herein allows a gradual transfer of the forces applied to the resin blade shell 7 to the metal attachment members, affording a convenient stiffness and avoiding the occurrence of vibration phenomena and elastic instability.
  • the blade shell may have more than two internal longitudinal struts 11, and the attachment root of the blade may have more than two arms 19 embedded in the plastics material of the struts 11 and connected to the cross-piece 21.

Abstract

A wind motor blade of composite construction has a blade shell of plastics material reinforced internally by transverse ribs and intersecting longitudinal struts in which metal fork arms are embedded, the fork arms being connected to a metal root attachment spigot through a metal cross-piece encapsulated in the plastics material.

Description

The present invention relates to blades for wind motors, in particular blades for attachment to a rotor hub of a wind motor.
It is known to fabricate blades for wind motors in light alloys such as aluminium alloys which have high strength and are weather-resistant. Such blades, however, have a considerable weight penalty, which in itself leads to undesirable stresses and deformations. Furthermore, the manufacturing cost of such blades is high.
It is also known to fabricate wind motor blades in synthetic resin material. Such blades, although of low weight and cost, present problems in the attachment of the blades to a rotor hub and in the incidence of aeroelastic vibrations.
An object of the present invention is to provide a blade for a wind motor having a secure connection between different materials such as metal and synthetic resin which have very different moduli of elasticity, so as to keep blade deformations under control, and to avoid in particular the occurrence of large amplitude aeroelastic vibrations.
The invention accordingly provides a blade for a wind motor having a metal attachment root, characterised in that the blade comprises a shell of plastics material having a number of internal transverse reinforcing ribs connected to at least two internal longitudinal members in which are embedded metal arms of the attachment root, which further includes a metal cross-piece to which said arms are attached, the attachment root also comprising a root member attached to said cross-piece for anchoring the blade to a rotor hub.
The blade construction according to the invention enables the wind loading exerted on the plastics blade shell to be transmitted through the ribs and longitudinal members to the metal cross-piece and thence to the attachment root member, with minimal blade deformation.
The invention will be further described, by way of non-limiting example, with reference to the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of a wind motor blade according to one embodiment of the invention, and
FIG. 2 is a cross-section taken on line II--II of FIG. 1.
With reference to the drawings, reference numeral 5 indicates generally a blade for a wind motor comprising a thin-walled shell of reinforced plastics material such as glass fibre reinforced plastics (g.r.p.) having an aerofoil section such as to be driven by wind flowing over the blade.
The blade 5 is supported internally by transverse ribs 9 the number of which will be chosen according to the length of the blade 5 and its desired rigidity. The internal ribs 9 also serve to reinforce the blade shell, avoiding the formation of local creases and ensuring a smooth blade profile during operation under wind loading. The ribs 9 are connected to internal longitudinal struts 11, also of a reinforced plastics material, which extend longitudinally within the blade shell and are connected to the internal surface of the blade shell along their opposite longitudinal edges.
The longitudinal struts 11, apart from having a blade-stiffening function, have chiefly a load-carrying function in that they transmit the load on the blade 5 to a rotor hub 13, shown partially in outline in FIG. 1 to which the blade is anchored by a metal fork attachment 15. Thus the wind loading applied to the blade shell 7 is transmitted through the ribs 9 to the internal struts 11, which in turn transmit the load to the hub 13 through the attachment 15.
The longitudinal struts 11 are, at their ends adjacent the hub 13, formed as hollow legs 17 of box section in which respective metal arms 19 of the fork attachment 15 are embedded. The fork attachment arms 19 are of steel or other high strength material and are connected to a cylindrical cross-piece 21 of the same material, extending transversely between and projecting beyond the root ends of the arms 19. The cross-piece 21 is hollow, having opposite end walls beyond the fork arms 11 from which respective cylindrical end pins 23 project, coaxially with the axis of the cross-piece 21. The lengths of the two end pins 23 will generally be different from each other, being selected according to the blade configuration.
The cross-piece 21 and the end pins 23, including the parts of the arms 19 and spigot 25 attached to the cross-piece 21, are embedded in plastics material formed integrally with that of the blade shell 7 and struts 11.
A blade root spigot 25 is attached to the cross-piece 21 between the two arms 19 and projects longitudinally beyond the radially inner end of the blade for the purpose of anchoring the blade 5 to the hub 13. The spigot 25 can have any shape according to the type of application of the blade. In the illustrated embodiment the spigot 25 has a tapered frusto-conical shape and terminates in a screw-threaded shank for attachment of the spigot to the rotor hub 13. The axis of the spigot 25 coincides with the longitudinal barycentric axis of the blade profile.
In the illustrated embodiment there would be three blades 5 such as that shown in the drawings anchored to the rotor hub 13 and extending radially from the hub with their axes inclined at 120° to each other.
The lengths of the fork arms 19 will be selected according to the required stiffness of the blade and to the required capacity of the blade assembly to withstand the flexural stresses resulting from wind loadings in use of the blade.
The cross-piece 21 and the end pins 23, being embedded in resin material connected to the longitudinal struts 17, serve to react the centrifugal force exerted by the blade 5 during its rotation about the axis of the hub 13.
The plastics-metal attachment structure of the blade 5 described herein allows a gradual transfer of the forces applied to the resin blade shell 7 to the metal attachment members, affording a convenient stiffness and avoiding the occurrence of vibration phenomena and elastic instability.
It will be appreciated that in some practical embodiments of the blade, the blade shell may have more than two internal longitudinal struts 11, and the attachment root of the blade may have more than two arms 19 embedded in the plastics material of the struts 11 and connected to the cross-piece 21.

Claims (4)

I claim:
1. Blade for a wind motor, comprising, in combination:
a hollow blade shell of plastics material having a number of internal transverse reinforcing ribs and at least two internal longitudinal reinforcing ribs interconnecting said transverse reinforcing ribs;
a metal reinforcement and attachment member embedded in said plastics material adjacent the radially inner end of the blade;
said metal member having at least two metal arms completely embedded in said longitudinal reinforcing ribs respectively, a metal cross-piece interconnecting said arms completely embedded in said plastics material, and
a metal root member attached to said metal cross-piece and projecting longitudinally beyond the radially inner end of the blade for anchoring the blade to a rotor hub.
2. The blade defined in claim 1, wherein said root member has a frusto-conical shape tapering towards its free end.
3. The blade defined in claim 1, including two end pins extending transversely of the longitudinal axis of the blade from opposite ends of the cross-piece.
4. Blade defined in claim 3, wherein the cross-piece comprises a cylindrical member and the end pins comprise cylindrical pins extending coaxially with the axis of said cylindrical member.
US05/962,731 1977-12-05 1978-11-21 Blade for wind motors Expired - Lifetime US4278401A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT69727/77A IT1091214B (en) 1977-12-05 1977-12-05 BLADE FOR WIND ENGINES
IT69727A77 1977-12-05

Publications (1)

Publication Number Publication Date
US4278401A true US4278401A (en) 1981-07-14

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US05/962,731 Expired - Lifetime US4278401A (en) 1977-12-05 1978-11-21 Blade for wind motors

Country Status (9)

Country Link
US (1) US4278401A (en)
JP (1) JPS5486037A (en)
DE (1) DE2852447C3 (en)
FR (1) FR2410749A1 (en)
GB (1) GB2009330B (en)
IT (1) IT1091214B (en)
NL (1) NL7811664A (en)
NO (1) NO784047L (en)
SE (1) SE7812460L (en)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4339230A (en) * 1980-04-22 1982-07-13 Hercules Incorporated Bifoil blade
US4389162A (en) * 1979-05-25 1983-06-21 Messerschmitt-Boelkow-Blohm Gesellschaft Mit Beschraenkter Haftung Rotor blade comprising a plurality of individual sections
US5118257A (en) * 1990-05-25 1992-06-02 Sundstrand Corporation Boot attachment for composite turbine blade, turbine blade and method of making turbine blade
US5314309A (en) * 1990-05-25 1994-05-24 Anthony Blakeley Turbine blade with metallic attachment and method of making the same
ES2144336A1 (en) * 1996-11-15 2000-06-01 Torres Martinez M Blade for wind-powered generator
US20070105431A1 (en) * 2005-11-10 2007-05-10 General Electric Company Modular blades and methods for making same
US20080185754A1 (en) * 2007-01-19 2008-08-07 John Wirt Method and apparatus for molding composite articles
US20080314309A1 (en) * 1999-09-24 2008-12-25 Vec Industries, L.L.C. Boat and Method for Manufacturing Using Resin Transfer Molding
WO2009054837A1 (en) * 2007-06-25 2009-04-30 Windstor Power Co. Improved vertical axis wind system
US20100028162A1 (en) * 2008-08-01 2010-02-04 Vestas Wind Systems A/S Rotor blade extension portion having a skin located over a framework
CN101611225B (en) * 2007-01-16 2012-05-23 丹麦技术大学 Reinforced blade for wind turbine
EP2317127A3 (en) * 2009-10-30 2014-01-08 General Electric Company Wind turbine blades
WO2014006080A1 (en) 2012-07-03 2014-01-09 Fiberline A/S A method of producing an assembly for use in a fibre reinforced structural element
JP2015504136A (en) * 2012-01-20 2015-02-05 アンドリッツ・ヒュードロ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング Rotor blades for turbines
US9068559B2 (en) 2009-02-16 2015-06-30 Vestas Wind Systems A/S Rotor blade for a wind turbine and a method for making the same
RU2651894C2 (en) * 2016-04-29 2018-04-24 Андрей Сергеевич Голиков Fan

Families Citing this family (6)

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Publication number Priority date Publication date Assignee Title
FR2604753B1 (en) * 1986-10-07 1990-09-21 Lejeloux Sarl DEVICE FOR CONNECTING THE ROTOR TO THE MULTIPLIER OF AN AERO-GENERATOR, AND AERO-GENERATOR PROVIDED THEREWITH
US5253824A (en) * 1991-04-16 1993-10-19 General Electric Company Hollow core airfoil
GB2254892A (en) * 1991-04-16 1992-10-21 Gen Electric Hollow airfoil.
US5439354A (en) * 1993-06-15 1995-08-08 General Electric Company Hollow airfoil impact resistance improvement
GB2472460B (en) * 2009-08-07 2011-11-16 Gurit Wind or tidal turbine blade having an attachment
CN102734218B (en) * 2012-06-27 2014-10-22 中国航空工业集团公司沈阳发动机设计研究所 Structural design method for wide-chord hollow blade

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US1372086A (en) * 1917-08-22 1921-03-22 Edward N Breitung Propeller
DE702039C (en) * 1937-08-11 1941-01-29 Dornier Werke Gmbh Propeller or wind turbine blades made of molded synthetic resin with a metal frame
US2454200A (en) * 1944-10-16 1948-11-16 Singer Mfg Co Molded impeller
US2715598A (en) * 1952-12-16 1955-08-16 Bristol Aeroplane Co Ltd Methods of jointing surfaces by heathardening resins
US3028292A (en) * 1957-05-27 1962-04-03 Parsons Corp Method of manufacturing plastic rotor blades
US3554664A (en) * 1968-05-20 1971-01-12 Technology Uk Reinforced plastic blades
US3645481A (en) * 1970-04-22 1972-02-29 Lanier Ind Inc Airfoil structure
US3647317A (en) * 1970-03-19 1972-03-07 Fluor Prod Co Inc Fiberglass fan assembly
US3720481A (en) * 1971-04-28 1973-03-13 Avco Corp Means for forming and securing turbine compressor blades
US4081220A (en) * 1976-12-17 1978-03-28 United Technologies Corporation Semi-spar wound blade

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DE895280C (en) * 1943-10-03 1953-11-02 Ulrich Dr-Ing Huetter Hollow wing for wind turbines
GB639337A (en) * 1946-10-31 1950-06-28 Autogiro Co Of America Improvements in blade construction for aircraft sustaining rotors
FR1070262A (en) * 1952-02-02 1954-07-21 Chantiers De France Atel Hollow rotor blade with variable pitch, especially for wind motor rotors
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FR1216378A (en) * 1958-11-17 1960-04-25 Propellerbau Ges Haw & Co Deut Propeller blades
US3161238A (en) * 1962-07-05 1964-12-15 Howard P Key Helicopter rotor blade
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FR1387611A (en) * 1964-03-24 1965-01-29 Bolkow Entwicklungen Kg Rotor blade for rotary wing machines
FR1492333A (en) * 1966-07-18 1967-08-18 United Aircraft Corp Composite blade for a helicopter rotor
DE2327393A1 (en) * 1972-05-31 1973-12-13 United Aircraft Corp COMPOSITE HELICOPTER ROTOR BLADE
DE2658876C3 (en) * 1976-12-24 1983-11-10 Hütter, Ulrich, Prof. Dr.-Ing., 7312 Kirchheim Shell bodies, for example hydrofoils or rotor blades, in composite construction

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1372086A (en) * 1917-08-22 1921-03-22 Edward N Breitung Propeller
DE702039C (en) * 1937-08-11 1941-01-29 Dornier Werke Gmbh Propeller or wind turbine blades made of molded synthetic resin with a metal frame
US2454200A (en) * 1944-10-16 1948-11-16 Singer Mfg Co Molded impeller
US2715598A (en) * 1952-12-16 1955-08-16 Bristol Aeroplane Co Ltd Methods of jointing surfaces by heathardening resins
US3028292A (en) * 1957-05-27 1962-04-03 Parsons Corp Method of manufacturing plastic rotor blades
US3554664A (en) * 1968-05-20 1971-01-12 Technology Uk Reinforced plastic blades
US3647317A (en) * 1970-03-19 1972-03-07 Fluor Prod Co Inc Fiberglass fan assembly
US3645481A (en) * 1970-04-22 1972-02-29 Lanier Ind Inc Airfoil structure
US3720481A (en) * 1971-04-28 1973-03-13 Avco Corp Means for forming and securing turbine compressor blades
US4081220A (en) * 1976-12-17 1978-03-28 United Technologies Corporation Semi-spar wound blade

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4389162A (en) * 1979-05-25 1983-06-21 Messerschmitt-Boelkow-Blohm Gesellschaft Mit Beschraenkter Haftung Rotor blade comprising a plurality of individual sections
US4339230A (en) * 1980-04-22 1982-07-13 Hercules Incorporated Bifoil blade
US5118257A (en) * 1990-05-25 1992-06-02 Sundstrand Corporation Boot attachment for composite turbine blade, turbine blade and method of making turbine blade
US5314309A (en) * 1990-05-25 1994-05-24 Anthony Blakeley Turbine blade with metallic attachment and method of making the same
ES2144336A1 (en) * 1996-11-15 2000-06-01 Torres Martinez M Blade for wind-powered generator
US20080314309A1 (en) * 1999-09-24 2008-12-25 Vec Industries, L.L.C. Boat and Method for Manufacturing Using Resin Transfer Molding
US7533626B2 (en) 1999-09-24 2009-05-19 Vec Industries, L.L.C. Boat and method for manufacturing using resin transfer molding
US20100025893A1 (en) * 1999-09-24 2010-02-04 Vec Industries, L.L.C. Method of manufacturing using resin transfer molding
US20070105431A1 (en) * 2005-11-10 2007-05-10 General Electric Company Modular blades and methods for making same
US7393184B2 (en) 2005-11-10 2008-07-01 General Electric Company Modular blades and methods for making same
CN101611225B (en) * 2007-01-16 2012-05-23 丹麦技术大学 Reinforced blade for wind turbine
US20080185754A1 (en) * 2007-01-19 2008-08-07 John Wirt Method and apparatus for molding composite articles
US8845947B2 (en) 2007-01-19 2014-09-30 Vec Industries, L.L.C. Method and apparatus for molding composite articles
US7785518B2 (en) 2007-01-19 2010-08-31 Vec Industries, L.L.C. Method and apparatus for molding composite articles
US20100327496A1 (en) * 2007-01-19 2010-12-30 Vec Industries, L.L.C. Method and apparatus for molding composite articles
WO2009054837A1 (en) * 2007-06-25 2009-04-30 Windstor Power Co. Improved vertical axis wind system
US20100028162A1 (en) * 2008-08-01 2010-02-04 Vestas Wind Systems A/S Rotor blade extension portion having a skin located over a framework
US8393865B2 (en) * 2008-08-01 2013-03-12 Vestas Wind Systems A/S Rotor blade extension portion having a skin located over a framework
US9068559B2 (en) 2009-02-16 2015-06-30 Vestas Wind Systems A/S Rotor blade for a wind turbine and a method for making the same
EP2317127A3 (en) * 2009-10-30 2014-01-08 General Electric Company Wind turbine blades
JP2015504136A (en) * 2012-01-20 2015-02-05 アンドリッツ・ヒュードロ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング Rotor blades for turbines
WO2014006080A1 (en) 2012-07-03 2014-01-09 Fiberline A/S A method of producing an assembly for use in a fibre reinforced structural element
US9895850B2 (en) 2012-07-03 2018-02-20 Fiberline A/S Method of producing an assembly for use in a fibre reinforced structural element
RU2651894C2 (en) * 2016-04-29 2018-04-24 Андрей Сергеевич Голиков Fan

Also Published As

Publication number Publication date
FR2410749B1 (en) 1982-03-26
NO784047L (en) 1979-06-06
NL7811664A (en) 1979-06-07
DE2852447C3 (en) 1981-08-20
DE2852447B2 (en) 1981-01-08
FR2410749A1 (en) 1979-06-29
DE2852447A1 (en) 1979-06-07
GB2009330B (en) 1982-02-10
IT1091214B (en) 1985-07-06
SE7812460L (en) 1979-06-06
JPS5486037A (en) 1979-07-09
GB2009330A (en) 1979-06-13

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Owner name: FIAT SOCIETA PER AZIONI, 10 CORSO MARCONI, TURIN,

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